@Mahitha The Microsoft.ServiceBus namespaces/queues section remains same for both standard and premium namespace. The document has the description of the object and name that are supported.
For your reference I have created the ARM template using the document which creates the premium namepace and one queue under your premium namespace. You can modify it as per your requirement.
Update:
To define the Max message size (in KB) you need to define maxMessageSizeInKilobytes
in your ARM template. I have reached out to the docmentation team to reflect the same.
Update 9/30: The document changes are reflected in the latest API version 2021-06-01-preview. Please leverage the latest API version.
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